std::fdim

From Cppreference

C++ Standard Library
Language Utilities library Strings library Containers library Algorithms library Iterators library Numerics library Input/output library Localizations library Regular expressions library (C++11) Atomic operations library (C++11) Thread support library (C++11)
Numerics library
Common mathematical functions
Functions Basic operations abs(int) labs llabs imaxabs (C++11) abs(float) fabs div ldiv lldiv imaxdiv (C++11) fmod remainder (C++11) remquo (C++11) fma (C++11) fmax (C++11) fmin (C++11) fdim (C++11) nan nanf nanl (C++11) (C++11) (C++11) Exponential functions exp exp2 (C++11) expm1 (C++11) log log10 log1p (C++11) log2 (C++11) Power functions sqrt cbrt (C++11) hypot (C++11) pow Trigonometric and hyperbolic functions sin cos tan asin acos atan atan2 sinh cosh tanh asinh (C++11) acosh (C++11) atanh (C++11) Error and gamma functions erf (C++11) erfc (C++11) lgamma (C++11) tgamma (C++11) Nearest integer floating point operations ceil floor round lround llround (C++11) (C++11) (C++11) trunc (C++11) nearbyint (C++11) rint lrint llrint (C++11) (C++11) (C++11) Floating point manipulation functions ldexp scalbn scalbln (C++11) (C++11) ilogb (C++11) logb (C++11) frexp modf nextafter nexttoward (C++11) (C++11) copysign (C++11) Classification fpclassify (C++11) isfinite (C++11) isinf (C++11) isnan (C++11) isnormal (C++11) signbit (C++11) Macro constants HUGE_VALF HUGE_VAL HUGE_VALL (C++11) (C++11) FP_NORMAL FP_SUBNORMAL FP_ZERO FP_INFINITE FP_NAN (C++11) (C++11) (C++11) (C++11) (C++11)

Defined in header <cmath>
float       fdim( float x, float y );	(1)	(since C++11)
double      fdim( double x, double y );	(2)	(since C++11)
long double fdim( long double x, long double y );	(3)	(since C++11)
Promoted    fdim( Arithmetic x, Arithmetic y );	(4)	(since C++11)

Returns the positive difference between x and y. This could be implemented as fmax (x - y, 0), so if x ≤ y, the result is always equals to 0, otherwise it is x - y.

4) If any argument has integral type, it is cast to double. If any other argument is long double, then the return type is long double, otherwise it is double.

[edit] Parameters

x, y

-

floating point value

[edit] Return value

The positive difference value.

[edit] See also

abs(int) labs llabs imaxabs (C++11)	computes absolute value of an integral value (|x|) (function)
fmax (C++11)	larger of two floating point values (function)